The statements in this section merely provide background information related to the present invention and may not necessarily constitute prior art.
A checkout system is known from DE 10 2004 040 856 A1 for handling sales or payment transactions which includes a housing as the central structural unit in which are located a computer module for the electronic processing of payment-related data and a hard disk as the peripheral module which can be detachably connected to the computer module. The computer module is configured as a motherboard on which the central unit is located. The hard disk is located displaceably in a compartment in the housing of the computer module so that it is possible to replace the hard disk relatively easily for service purposes. However, the hard disk is mounted in a frame which is attachable to the computer module by means of threaded fasteners. The disadvantage thereof is that replacement of the peripheral module is possible only with the aid of a tool for threaded fasteners.
A computer system is known from U.S. Pat. No. 4,501,460 in which a computer module can be latched or unlatched without the aid of a tool, using a peripheral module configured as a storage medium. However, the latching mechanism provided for this purpose includes a lever mechanism and a latch bar extending along one housing wall of the computer module which can be moved reciprocally lengthwise by means of the lever mechanism between a locking (capturing) position and an unlocking (accommodating) position. In the latched position, hooking members on the peripheral module are engaged in corresponding recesses in the housing wall of the computer module. In the latched position, the peripheral module makes electrical contact with the computer module by way of an electrical plug device. In the unlatched position, the hooking members of the computer module are brought to a disengaged position relative to the recesses on the computer module so that the peripheral module is separated from the computer module, from a contacting position in which mutually facing housing walls of the computer module and the peripheral module immediately adjoin each other. The disadvantage of the known computer system is that the latching mechanism has a relatively complex configuration. The space it requires in particular is relatively large.